[Palaeontology, Vol. 50, Part 5, 2007, pp. 1051–1071] NEOSELACHIANS FROM THE UPPER CAMPANIAN AND LOWER MAASTRICHTIAN (UPPER View metadata, citation and similar papers at core.ac.uk brought to you by CORE CRETACEOUS) OF THE SOUTHERN PYRENEES, provided by EPrints Complutense NORTHERN SPAIN by JU¨ RGEN KRIWET*, RODRIGO SOLER-GIJO´ N* and NIEVES LO´ PEZ-MARTI´NEZ *Museum of Natural History, Palaeontology, Humboldt-University of Berlin, Invalidenstraße 43, 10115 Berlin, Germany; e-mails: [email protected], [email protected] Department Palaeontologı´a, Fac. C. Geolo´gicas, Universidad Complutense de Madrid, 28040 Madrid, Spain; e-mail: [email protected] Typescript received 24 May 2006; accepted in revised form 4 September 2006 Abstract: Bulk sampling of upper Campanian to lower– assemblages known from the marine Upper Cretaceous, but middle Maastrichtian coastal and lagoonal deposits in five differs from nearby localities of the Basque-Cantabrian region sections of the Tremp Formation in the south-central Pyrenees and continental selachian associations of the French Pyrenees. yielded numerous neoselachian teeth. The fauna comprises The results indicate that Rhombodus might not be a reliable nine taxa of which three species and one genus are new: biostratigraphic marker for the Maastrichtian. The faunal Hemiscyllium sp., Lamniformes indet., Paratrygonorrhina composition suggests a shallow trans-Tethyan connection amblysoda gen. et sp. nov., Coupatezia trempina sp. nov., between Eurasia and India at the end of the Cretaceous Period. Coupatezia sp., Coupatezia? sp., Rhombodus ibericus sp. nov. and Igdabatis indicus. The neoselachian fauna is dominated Key words: biostratigraphy, Late Cretaceous, Neoselachii, by small nectobenthic rays. This composition resembles palaeoecology, palaeogeography, Pyrenees, Spain. Late Cretaceous selachian diversity is remarkably high screen-washing of suitable sediments enabled Soler-Gijo´n (e.g. Kriwet and Benton 2004) and many taxa have been and Pen˜a (1995), Pen˜a and Soler-Gijo´n (1996), Pen˜a described from numerous Late Cretaceous and Palaeo- (1997) and Soler-Gijo´n and Lo´pez-Martı´nez (2005) to gene sites. Important selachian assemblages have been report several actinopterygians, and Soler-Gijo´n and reported from phosphatic deposits of the southern Lo´pez-Martı´nez (1995, 1998) indicated the presence of Mediterranean belt that crop out from North Africa to six chondrichthyan taxa in upper Campanian–lower the Middle East (e.g. Arambourg 1952; Cappetta 1987; Maastrichtian red beds of the Tremp-Gaus Basin, located Noubhani and Cappetta 1997; Bardet et al. 2000; Cap- in the south-central Pyrenees of northern Spain. Addi- petta et al. 2000; Mustafa 2000; Antunes and Cappetta tionally, Cappetta and Corral (1999) described 19 taxa 2002), and also from central and northern Europe and from the terminal Maastrichtian of the Basque-Cantabrian the Eurasian platform (e.g. Herman 1977a, 1982; Bor region, Gheerbrant et al. (1997) reported some selachians 1983; Landemaine 1991; Siverson 1992, 1993; Radwan´ ski from the Campanian–Maastrichtian in the French part and Marcinowski 1996; Trbusˇek 1999; Siverson and of the Pyrenees, and Cappetta and Odin (2001) reported Cappetta 2001; Vullo 2005) and the USA (e.g. Case and selachians of the same age from south-east France. Cappetta 1997; Cappetta and Case 1999). Conversely, Mendiola and Martinez (2003) summarized current data concerning selachians from the end of the Creta- knowledge of Mesozoic and Cenozoic selachians from ceous in Spain and southern France are very incomplete. Spain and listed 21 Maastrichtian taxa. Despite the wide distribution of Late Cretaceous sedi- The taxonomic composition of the selachian assem- ments on the Iberian Peninsula only a few references to blage from Lleida in the south-central Pyrenees, especi- fishes had been published up to the 1990s. New research ally the presence of Igdabatis indicus Prasad and conducted in the last two decades in combination with Cappetta, 1993, was taken as evidence of biogeographical ª The Palaeontological Association doi: 10.1111/j.1475-4983.2007.00695.x 1051 1052 PALAEONTOLOGY, VOLUME 50 relationships between Eurasia and Gondwana at the K ⁄ T 1993; Alvarez-Sierra et al. 1994; Lo´pez-Martı´nez et al. boundary by Soler-Gijo´n and Lo´pez-Martı´nez (1998). In 2001). addition to Igdabatis, they listed Lissodus, Hemiscyllium, Here, we describe neoselachian remains from five local- an undetermined lamnid shark, Rhinobatos and Rhombo- ities in Lleida province: Orcau 2 and Suterranya on the dus. However, these taxa have not been systematically northern flank of the Tremp syncline; Julı´ near Isona in described and are mostly unfigured so far. The relation- the central part of this syncline, and Fontllonga 6 and ships of this fauna to the slightly younger one of the Figuerola 2 in the Ager syncline (Text-fig. 1). The strati- Basque-Cantabrian region (Cappetta and Corral 1999) graphic correlation of the sites and fossiliferous sediments also remain unresolved. The intention of this paper is to in the two synclines is based on rudist and microfossil present a systematic account of the neoselachian assem- occurrences (Table 1). blages from the upper Campanian and lower Maastrich- tian of the Tremp Formation in the south-central Northern flank of the Tremp syncline. The fish remains of Pyrenees. the Orcau 2 site come from a greenish marly bed rich in bivalve moulds, which lies just above a conspicuous level comprising rudist shells of Praeradiolites bucheroni in life GEOLOGICAL SETTING AND position. These levels are c. 30 m above the contact of the STRATIGRAPHY Tremp Formation with the underlying Aren Sandstone, a few hundred metres to the east of the village of Orcau on The samples yielding neoselachian material come from the northern flank of the Tremp syncline (Text-fig. 1). the Tremp Formation near its type locality at Lleida, The contact between both formations is younger in Orcau where it is more than 900 m thick. The formation ranges itself, where the rudist bed lies directly on the Aren Sand- from late Campanian to early Eocene in age (Galbrun stone. This westward progradation pattern indicates that et al. 1993; Schmitz and Pujalte 2003) and comprises the Aren-Tremp contact is diachronous and corresponds mainly ochre and reddish clays and sandstones (Units 2 to sediments from a barrier island-lagoon depositional and 4), with grey marls and limestones in its lower and system, which moved westwards as the sea level rose middle parts (Units 1 and 3). These deposits, which crop (Nagtegaal et al. 1983; Dı´az Molina 1987; Arde`vol et al. out in most of the north and south Pyrenean regions, are 2000). usually considered to be fluvial and lacustrine in origin, The fish remains from the Suterranya site, 4 km west except for Unit 1 in the Isona area (some 15 km to the of Orcau (Text-fig. 1), come from a grey marl rich in east of Tremp) where rudists and corals are intercalated gypsum crystals, only accessible in an ancient coal mine with coal beds yielding abundant plant remains, indica- gallery, c. 10 m above the contact of the Tremp Forma- ting a marginal marine setting. A more or less strong tion with the Aren Sandstone. Rudist remains are marine influence is present through the entire formation, common here. The gypsiferous bed intercalates with indicating that near its type area it represents transitional coal-bearing grey marls, limestones and shell beds (mainly peritidal to coastal deposits (Dı´az Molina 1987; Rossi consisting of remains of the snail Melanoides and the TABLE 1. Stratigraphic position and age of the fossiliferous localities of the Tremp Formation (data partially from Soler-Gijo´n and Lo´pez-Martı´nez 1995, 1998). Locality Stratigraphic position Position in rudist Age and criteria in the Tremp Formation biostratigraphy Orc-2 30 m above the base (unit 1) just above upper H. castroi uppermost Campanian, sequence stratigraphic horizon correlation below the middle G. gansseri planktic foraminiferal biozone Sut 10 m above the base (unit 1) just above upper H. castroi as above horizon Julı´ 135 m above the base 20 m above upper H. castroi upper Campanian, sequence stratigraphic (top unit 1) horizon correlation well below middle G. gansseri planktic foraminiferal biozone Fig-2 70 m above the base 70 m above R. pulchella upper Campanian, magnetostratigraphic (top unit 1) horizon correlation with chron c32 or c33 Font-6 95 m above the base 95 m above R. pulchella lower Maastrichtian, magnetostratigraphic (lower part of unit 2) horizon correlation with chron c31r KRIWET ET AL.: NEOSELACHIANS FROM THE UPPER CRETACEOUS OF NORTHERN SPAIN 1053 N 2 1 Tremp 3 Tremp syncline Isona Montsec Ager syncline 5 4 TEXT-FIG. 1. Map of the Tremp and Ager areas in the southern Pyrenees (northern Spain) and locations of fossil fish sites in the synclines. 1, Orcau 2; 2, Suterranya; 3, Julı´; 4, Figuerola 2; 5, Fontllonga 6. clam Cyrena). Here, the Tremp-Aren contact is appar- boundary horizon, approximately dated to the Campa- ently complicated by a phase of sea-level fall (see Arde`vol nian ⁄ Maastrichtian boundary, is situated more than et al. 2000, fig. 11: lagoonal deposit between sections 3 200 m above it. and 4). The rudist levels underlying the fish level at Orcau and Ager syncline. The Ager syncline is located to the south of Suterranya have been correlated with the upper Hippuri- the Tremp syncline and is separated from it by the Mont- tella castroi horizon by Vicens et al. (2004). sec anticline (Text-fig. 1). Here, the Tremp Formation It has been possible to estimate the age of the Orcau 2 reaches c. 700 m in thickness and lies conformably above and Suterranya fish levels based on their positions within shallow marine calcarenite deposits of the Les Serres the sequence-stratigraphic succession of Arde`vol et al.